But making the vaccine involves dissecting mosquitos by hand.

Several vaccines for malaria have been developed over the past few decades, but none offer complete protection. Now, for the first time, US researchers have developed a vaccine that protects 100 percent of those given five doses of the vaccine, albeit in a very small trial.

Malaria is caused by Plasmodium parasites. It affects more than 200 million people annually and, according to the World Health Organisation, it killed 660,000 people in 2010, most of them children. GlaxoSmithKline's Mosquirix is the most advanced malaria vaccine currently being tested. It protects against Plasmodium falciparum, the most deadly of the parasites.

But as Brian Greenwood of the London School of Hygiene and Tropical Medicine told The Conversation, "Mosquirix is only about 50% effective when given to older children and even less effective (about 30 percent) when given to young infants with routine vaccines. A better vaccine with a higher level of protection is needed."

The new vaccine, dubbed PfSPZ, has been developed by Sanaria, a US biotech firm, in collaboration with the National Institutes of Health (NIH). Like Mosquirix, it attacks the first stage of malaria called "pre-erythrocytic", and may stem the disease before symptoms show. But unlike Mosquirix, which is made of proteins from the parasite’s surface, PfSPZ consists of sporozoites (a young form of the malarial parasites) that have been weakened by irradiation.

Sanaria's concoction was tested in 44 volunteers two years ago by delivering the sporozoites through an injection into the skin. But only two of them developed the required immunity. Later animal studies by Robert Seeder of NIH showed that delivering the vaccine by injecting it directly in veins was more effective.

This is what Sanaria has done in the new trials. Each of its injections consisted of 135,000 irradiated sporozoites. Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria. None of the six who were given five doses developed the disease.

The number of patients involved is tiny. Greenwood warns, "This is only a proof-of-principle study, although a very important one, and the experiment will need to be repeated on a larger number of subjects before it can be taken into field trials in malaria endemic areas."

And scaling up is not going to be easy. Currently, the sporozoites are extracted from mosquitoes manually. Sanaria has employed 15 "dissectors" who can each tear open about 150 mosquitoes per hour. The process will need to be automated if PfSPZ is to make it to the market.

The limitations go further. PfSPZ needs to be stored in liquid nitrogen containers and without five doses it cannot produce 100 percent protection. Those doses need to be delivered intravenously, which is difficult to do in infants and requires trained professionals for older children.

All this makes the vaccine, in its current form, expensive and impractical for a disease that affects the world's poorest people. "However, the problems are not insurmountable and there may be technical ways of addressing this challenge," Greenwood said.

Adrian Hill, professor of human genetics at the University of Oxford, welcomes Sanaria's vaccine but feels he may have a better solution. His research group is working on combining Mosquirix with another vaccine to make a mixture that he believes could be as effective as PfSPZ and won't have the same limitations.

"Mosquirix attacks the first half of the pre-erthyrocytic stage," he said. "Our vaccine attacks the second half of that stage using a viral vector to deliver the antigen (a molecule that activates the immune system). It is this combination that may do the trick."

Sanaria's results, published in the Science today, are at the very beginning of the vaccine development. There are many other vaccines at various stages of development intermediate between that of the Sanaria vaccine and Mosquirix. "These other vaccines may come to market quicker than PfSPZ, given its limitations," said Hill, who is optimistic something good will emerge from them. "If all goes well, by 2020, we should have a cheap and effective malaria vaccine."

Cool, but if it requires freezing and multiple doses it's really only going to protect the well-off. I saw elsewhere that the sample size was so low (6!) so I was skeptical about the 100% success rating, but I hadn't seen that the success fell off so sharply with just 4 out of 5 injections or that freezing was necessary. Those are really major limitations.

Well, 6/6 is enough to know you're doing better than 50%. However, even if it's not an effective regime at least we know it's a vector to a cure. As my advisor in grad. school used to say the important part is to know that A solution exists. After that it's optimization - something that can be done incrementally.

I imagine finding extra dissectors shouldn't be hard. I for one would probably volunteer some of my off-hours for an activity that lets me murder hundreds of damn mosquitos with a knife or other sharp implement.

Well, 6/6 is enough to know you're doing better than 50%. However, even if it's not an effective regime at least we know it's a vector to a cure. As my advisor in grad. school used to say the important part is to know that A solution exists. After that it's optimization - something that can be done incrementally.

1/1 is also better than 50%.

Exaggerated Ars headlines aside, 6/6 does not come close to proving that the vaccine "offers complete protection." It only shows that it is worth investing in slightly larger scale trials.

Knowing a 100% effective vaccine is possible and the method. Showing it is possible and the method. This is where money get spent on it. It is very low hanging fruit. Playing with and sorting through what works and what doesn't won't take too long and something many teams can work on.

How to industrialize and make it cheaper. Adding activators. Getting partial sequences or artificial DNA chains to synthesize. This hopefully won't take long and will improve quickly over time.

We are in the golden age of health care. Science is understanding how everything works at a basic level.

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

not sure how they contracted it, but the article sounds like those 9 volunteers were only going to get 4 injections.

also isnt PfSPZ the sound the mosquito makes when it hits a bug zapper?

Making the vaccine could be considered an act of revenge, since it involves killing hundreds of mosquitos.

I am totally fine with that.

Malaria has a devastating effect in parts Africa already blighted by drought, famine, war and more recently HIV/AIDS. It has been claimed that Malaria is a cause of poverty. It is a serious development issue. A better standard of living is difficult to achieve if you are dirt poor, living a subsistence life and cannot farm because you and the animals you eat or that plough your fields fall ill to this disease.

Malaria sits atop a pyramid of woes and its eradication is long overdue.

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

If it actually works as well as advertised in a larger sample size and could be made available the way that other vaccines like smallpox or polio were, it could be huge for human health.

It's important to keep in mind that malaria is only going to be a bigger issue as populations rise, as the planet warms (more mosquito going further north), and as the parasite itself becomes resistant to many of the drugs used today to treat it.

Well, 6/6 is enough to know you're doing better than 50%. However, even if it's not an effective regime at least we know it's a vector to a cure. As my advisor in grad. school used to say the important part is to know that A solution exists. After that it's optimization - something that can be done incrementally.

1/1 is also better than 50%.

Exaggerated Ars headlines aside, 6/6 does not come close to proving that the vaccine "offers complete protection." It only shows that it is worth investing in slightly larger scale trials.

I think you are missing some basic statistical knowledge here. The comment you quoted said that success rate of the cure must be way above 50% to achieve a 6/6 ratio. He is probably correct since a cure with 50% success rate would have a probability of 0.0156250 to cure 6 people. A cure with say an 80% average success rate might have cured 6/6 of people with a probability of 0.2621440. If the cure would successfully immunize 95% of its tested persons the chance of it curing 6/6 persons is 0.7350919.

So there you have it, it might be a very small sample size it definitely indicates that this vaccination procedure probably has a very high success rate. Even though it is currently a very lengthy process to vaccinate a single person..

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

From the paper: those 9 volunteers were scheduled for four doses only. After the doses were done, the disease was artificially induced in the volunteers, but only 3 of the 9 contracted it. The others had become immune.

I think you are missing some basic statistical knowledge here. The comment you quoted said that success rate of the cure must be way above 50% to achieve a 6/6 ratio. He is probably correct since a cure with 50% success rate would have a probability of 0.0156250 to cure 6 people. A cure with say an 80% average success rate might have cured 6/6 of people with a probability of 0.2621440. If the cure would successfully immunize 95% of its tested persons the chance of it curing 6/6 persons is 0.7350919.

So there you have it, it might be a very small sample size it definitely indicates that this vaccination procedure probably has a very high success rate. Even though it is currently a very lengthy process to vaccinate a single person..

Took the words right out of my mouth. 6/6 is good, but not nearly solid enough to call it 100% effective.

Let those that say that drug companies are only interested in plying the first world with expensive drugs read this article and feel a wave of warmth for the human race. If the difficulties can be ironed out then I hope we see a worldwide concerted effort to eradicate malaria once and for all.

Apparently a lot of you missed the part of the article where the researcher said that it is a PROOF OF CONCEPT study, albeit a very important one. No one is saying this is definitive. It's just another wonderful step and success for science in the long road of eliminating the threat malaria.

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

Reading other sources, what happened is that some of the volunteers got different course of the IV vaccines. At the end, they were deliberately exposed to live malaria, which should have infected (nothings perfect though) 100% of the volunteers.

9 volunteers received 4 doses each at 1 month intervals and were then exposed to malaria, 3 of them got sick and 6 did not.

6 volunteers received 5 doses each at 1 month intervals and were then exposed to malaria, none of them got sick.

I'd be curious if a higher load of weakened malaria, but fewer courses would work the same, or higher load, but longer interval and fewer courses. I guess stuff to play with in follow on trials.

I am also really curious about the mention of combining the two potenial vaccines. Hopefully at some point an IM deliverable vaccine that doesn't require more than 3 vaccinations can be developed. Things like LN storage are obviously huge limitations still, but I think the two biggest are having to be IV administered and the large number of doses required, especially as an IV vaccination. Storage requirements I think are slightly secondary to this.

Of course if other changes can be made, such as storage can be at room temperature for extended periods (I'd assume 60 days would be the minimum required to be considered "good to store at room temperature") and a single dose to provide 80+% efficacy, then being IV only is much less of a handicap.

Knowing a 100% effective vaccine is possible and the method. Showing it is possible and the method. This is where money get spent on it. It is very low hanging fruit. Playing with and sorting through what works and what doesn't won't take too long and something many teams can work on.

How to industrialize and make it cheaper. Adding activators. Getting partial sequences or artificial DNA chains to synthesize. This hopefully won't take long and will improve quickly over time.

We are in the golden age of health care. Science is understanding how everything works at a basic level.

This seems a bit optimistic, but I would like to think its all true.

I haven't read the study, but I am a bit concerned that the 3 out of the original 9 who started the study got malaria. Are we sure that it wasn't from the 4 inoculations they already received? I'm sure someone can (has?) answer this.

As to living in a golden age of medicine, I'm not convinced. It seems more like we're at the end of one. After all, our biggest guns, the antibiotics, are becoming less effective (think MRSA.)

Here's to the possible beginning of the end to malaria. Always hope for the best!

"Only three of the nine volunteers who were given four of these injections at one-month intervals developed malaria."

Does this mean that they developed malaria before the fifth injection was scheduled? Did they contract the disease because of the injections of the vaccine or were the test individuals exposed to the disease separately from these injections?

From the paper: those 9 volunteers were scheduled for four doses only. After the doses were done, the disease was artificially induced in the volunteers, but only 3 of the 9 contracted it. The others had become immune.

So I'm assuming a different 6 people received 5 doses? Because it seems silly at this stage to give the 6 from the original group that were immune another dose and then check to see if they're still immune.

I haven't read the study, but I am a bit concerned that the 3 out of the original 9 who started the study got malaria. Are we sure that it wasn't from the 4 inoculations they already received? I'm sure someone can (has?) answer this.

From the paper: A total 40 participants were vaccinated at least once (36/40 received all scheduled vaccinations).

study authors wrote:

Vaccinations were well-tolerated and there were no breakthrough malaria infections prior to controlled human malaria infection (CHMI) (Table 1).

5 of 6 non-vaccinated controls developed malaria after CHMI, compared to 3 of 9 receiving 4 doses, and 0 of 6 receiving 5 doses. The participants in each group were different.

Knowing a 100% effective vaccine is possible and the method. Showing it is possible and the method. This is where money get spent on it. It is very low hanging fruit. Playing with and sorting through what works and what doesn't won't take too long and something many teams can work on.

How to industrialize and make it cheaper. Adding activators. Getting partial sequences or artificial DNA chains to synthesize. This hopefully won't take long and will improve quickly over time.

We are in the golden age of health care. Science is understanding how everything works at a basic level.

This seems a bit optimistic, but I would like to think its all true.

I haven't read the study, but I am a bit concerned that the 3 out of the original 9 who started the study got malaria. Are we sure that it wasn't from the 4 inoculations they already received? I'm sure someone can (has?) answer this.

As to living in a golden age of medicine, I'm not convinced. It seems more like we're at the end of one. After all, our biggest guns, the antibiotics, are becoming less effective (think MRSA.)

Here's to the possible beginning of the end to malaria. Always hope for the best!

Yes, we are sure they didn't get malaria from the innoculations. Why?

1) They've done previous testing with weakened sporozoites, and no one got malaria from them.

2) The vaccine was given over the course of 3 months. Then the patients were exposed to full-strength malaria pathogens some period of time after the last vaccine injection. Malaria has a 8-25 day incubation period, so they have a pretty good idea which exposure caused the actual disease. Plus, in vaccine trials with live pathogens, they usually take pretty frequent blood tests to do things like measure antibody levels and see if the weakened pathogen is behaving as expected (there have been problems in the past with weakened pathogens not quite being weakened enough).

This study is far from the final word on this vaccine. And it raises lots of interesting questions. But "did the vaccine cause the malaria" is not one of them.

Things like LN storage are obviously huge limitations still, but I think the two biggest are having to be IV administered and the large number of doses required, especially as an IV vaccination. Storage requirements I think are slightly secondary to this.

Having been part of hospital programs to deliver vaccinations, you have this a bit backwards. Storage requirements are one of the most important characteristics of vaccinations. Think about the logistics of making sure something stays at ~-200C at every step of the supply chain between a manufacturer all the way to the end patient at a hospital or clinic. Liquid nitrogen itself is easy enough to procure in most metropolitan areas, but the storage containers, especially at the delivering clinic and at distribution points in the supply chain are bulky, fragile and expensive. The need for frequent LN resupply is also a significant constraint. Remember also that, at least in much of the US, refrigeration equipment for use in clinical activity is supposed to be monitored, checked, and serviced relatively frequently (I'm not saying this is always done, a lot of small doctors clinics do not do as much servicing as they should) to ensure that medications/vaccines don't exceed storage temps and be rendered less active than they should be. I've had clinics associated with large hospital networks that take months to get simple 4C fridge.

Comparatively, the pain (quite literally) of finding a patient's vein for an injection, and scheduling several frequent followup visits, may be significant barriers to adoption, but they're nothing nearly as bad. (I'm not saying they're not problems, they're just not as big).

1. What will happen, now that there will 600K less (assuming 100% immunization rate) people dying? (in terms of resource utilization, sanitary conditions etc... looks like malaria will be replaced by cholera)

2. Why no one is trying to address the real issue here - overpopulation is forcing people to encroach upon territory plagued by mosquitoes.

1. What will happen, now that there will 600K less (assuming 100% immunization rate) people dying? (in terms of resource utilization, sanitary conditions etc... looks like malaria will be replaced by cholera)

1. What will happen, now that there will 600K less (assuming 100% immunization rate) people dying? (in terms of resource utilization, sanitary conditions etc... looks like malaria will be replaced by cholera)

2. Why no one is trying to address the real issue here - overpopulation is forcing people to encroach upon territory plagued by mosquitoes.

Overpopulation has little to do with it. Malaria is endemic to the tropics, and those have been relatively populous long before our sheer numbers started to become an issue.

To add to the answer of Wheels of Confusion, if fewer people die of malaria, they will not just be more productive but also their eventual wealth will raise living standards of that part of the world and will lead to decline in the number of children born per woman. Something that Hans Rosling has explained beautifully: http://www.youtube.com/watch?v=ZnexjTCBksw

Wow, there is dedication to volunteer to maybe catch Malaria. Considering the huge annual profits of the related corporation, one would hope that those who got Malaria got some sort of cash donation afterwards from their corporate sponsor, as well as free medical care for their shortened lives.

Well, 6/6 is enough to know you're doing better than 50%. However, even if it's not an effective regime at least we know it's a vector to a cure. As my advisor in grad. school used to say the important part is to know that A solution exists. After that it's optimization - something that can be done incrementally.

1/1 is also better than 50%.

Exaggerated Ars headlines aside, 6/6 does not come close to proving that the vaccine "offers complete protection." It only shows that it is worth investing in slightly larger scale trials.

I think you are missing some basic statistical knowledge here. The comment you quoted said that success rate of the cure must be way above 50% to achieve a 6/6 ratio. He is probably correct since a cure with 50% success rate would have a probability of 0.0156250 to cure 6 people. A cure with say an 80% average success rate might have cured 6/6 of people with a probability of 0.2621440. If the cure would successfully immunize 95% of its tested persons the chance of it curing 6/6 persons is 0.7350919.

So there you have it, it might be a very small sample size it definitely indicates that this vaccination procedure probably has a very high success rate. Even though it is currently a very lengthy process to vaccinate a single person..

Most likely, but it is important to remember that:1. Flukes do happen2. Sometimes a person fights of malaria without any immunization at all (for example, 1 out of the 6 in their very own control group resisted being infected without any treatment)

That being said, your math is correct and this is extremely promising. I would certainly bet money on it being over 50% effective

Wow, there is dedication to volunteer to maybe catch Malaria. Considering the huge annual profits of the related corporation, one would hope that those who got Malaria got some sort of cash donation afterwards from their corporate sponsor, as well as free medical care for their shortened lives.

Malaria is highly curable when (i) caught early, (ii) the appropriate treatments are used, and (iii) blood tests are used to ensure complete clearance of the pathogen. Presumably, in such a clinical setting they are providing such treatment. Complications over the course of a lifetime are extremely rare for people who get modern treatments.

Experimental vaccines/treatments always have some dangers, so I still tip my hat to participants, but it's not anywhere near as dangerous as you are making it out to be.

1. What will happen, now that there will 600K less (assuming 100% immunization rate) people dying? (in terms of resource utilization, sanitary conditions etc... looks like malaria will be replaced by cholera)

2. Why no one is trying to address the real issue here - overpopulation is forcing people to encroach upon territory plagued by mosquitoes.

The sociopathy hinted at by these questions is truly scary. A tiny bit of freelance googling would tell you that we know, conclusively, from multiple, massive, real life examples that less children dying of endemic diseases SLOWS population growth, not increases it. If you are sure your kids will have long, full lives, and be there to care for you in your twilight years, you have less of them. It's uncertainty that is a major driver of the rural poor having large families.